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Chinchillas
Chinchillas are rabbit-sized, crepuscular rodents native to the Andes mountains in South America. Along with their relatives, viscachas, they belong to the family Chinchillidae. History The animal (whose name literally means "little Chincha") is named after the Chincha people of the Andes, who wore its soft and dense fur. By the end of the 19th century, chinchillas had become quite rare due to hunting for their fur. Most chinchillas currently used by the fur industry for clothing and other accessories are farm-raised.http://www.chincare.com/HealthLifestyle/JEJ/JEJExtirpation1995.pdf The first literature reference to chinchillas dates back to 1590 in a book published in Seville, entitled Historia Natural y Moral de las Indias, written by Father José de Acosta: (from Spanish) "About mountain animals. Chinchillas are another type of small animals such as squirrels. They have a fur (coat) that is of wonderful softness". One of the first people to think of breeding chinchillas for profit was the Jesuit priest Juan Ignacio Molina, who was also the first person to provide an accurate description of Chinchilla in 1810. There were repeated attempts to breed these animals in captivity. The first reliable report of successful breeding attempt in captivity comes from Frederico Albert (1900), who was director of the zoological and botanical research station at Santiago, Chile. He reports in his article "La Chinchilla" about a certain Francisco Irrazaval in Santiago who had received a pair of chinchillas (presumably Chinchilla lanigera) in 1895. The first chinchilla was born that same year and the pair continued to produce 2 litters a year until the outbreak of an epidemic during the summer of 1896 ruined this excellent breeding success, and all the animals, 13 at that time, died within a period of two months. Mathias F. Chapman, a mining engineer from California, was working in Chile in 1918 when he purchased a chinchilla as a pet and took a liking to it. He envisioned raising a whole herd of chinchillas and he applied to the Chilean government for permission to capture and transport several animals to the US. At this point, chinchillas were already close to extinction from humans killing them for the fur trade. The Chilean government was reluctant to grant trapping permission, but Chapman persisted, and eventually the government allowed him to catch them. Chapman and a group of men searched the mountain for three years and caught only eleven chinchillas. He then took the 12,000 foot climb down over a period of twelve months so the chinchillas could acclimate to the changing environment. He then brought the eleven wild chinchillas he had captured to the United States for breeding, where he started the first chinchilla farm. Only three of these chinchillas were female. This was the beginning of the domestic chinchilla.http://chin.dk/eng/facts.html Since the mid-1960s, chinchillas have become increasingly popular as house pets. Native environment Chinchilla originate in the Andes Mountains of South America where they inhabit rock crevices.The origin of wild chinchillas is in the gigantic mountains of the Andes; in Chile, Peru, Bolivia, and Argentina chinchillas are at home. In this barren area, chinchillas live in crevices and rocky burrows, under extreme climatic conditions. They are subjected to considerable variations in temperature, long droughts as well as low humidity. They live on so-called puyas, among other things. Puya is a sort of plant which also serves as a source for water and nutrients and offers protectionhttp://chinchilla-care.com/ They are agile jumpers and can jump very high, up to 5 feet. Predators in the wild include hawks, skunks, felines, and canines. Chinchillas have a variety of defence tactics including spraying urine and releasing fur if bitten. In the wild chinchillas have been observed eating plants, fruits, seeds, and small insects, though this diet could irritate the digestive system of a domestic chinchilla whose diet should be primarily hay-based. In nature, chinchillas live in colonies. Chinchilla females are significantly bigger than males. Chinchillas can breed any time of the year. At 111 days, they have a very long gestation period compared to other rodents. Due to this long pregnancy, chinchillas are born fully furred and with eyes open. Litters are usually small in number, predominately twins. Chinchilla species There are two living species of chinchilla, Chinchilla brevicaudata and Chinchilla lanigera. There is little noticeable difference between the species except that the Chinchilla brevicaudata has a shorter tail, a thicker neck and shoulders, and shorter ears. This species is currently facing extinction. The Chinchilla lanigera species, though rare, can be found in the wild. Domestic chinchillas are thought to come from the lanigera species.http://animal-world.com/encyclo/critters/chinchilla/chinchilla.php The Giant Chinchilla species has been hunted to extinction.http://www.chinchillaburg.com/Burgindex/English1/english1.html Fur industry The international trade in chinchilla fur goes back to the 16th century. The fur from chinchillas is popular in the fur trade due to its extremely soft feel, because they have about 60 hairs sprouting from each hair follicle. The color is usually very even which makes it ideal for small garments or lining of large garments, though some large garments can be made entirely from the fur. The pelt of a chinchilla is relatively small, so many animals must be killed to make a single coat. This fact led to the extinction of one species, and put serious pressure on the other two. Though wild chinchillas are no longer hunted for their fur, domestic chinchillas are still bred for this use.http://www.endangeredspecieshandbook.org/trade_chinchillas.php Chinchillas as pets Domestic chinchillas can be kept as pets. Chinchillas are naturally skittish and are nocturnal, thus mostly active for play in the evening. They also have delicate bones and generally do not like to be held. Because of this they are not considered to be good pets for small children. However, Chinchillas can also be very friendly animals, making them excellent pets if their trust is earned by the owner. Also, unlike other small domestic rodents, chinchillas' excretions are easy to clean up because of their small, dry nature. Captive chinchillas commonly live 15 years, but some have been known to live up to 20 or more.http://exoticpets.about.com/cs/chinchillas/p/Chinchillas.htm Chinchillas make many noises, including barks, chirps, and squeaks. They use this variety of vocalisations to express themselves, from a calm, loving chirp given to a potential mate to a loud, aggressive bark when spooked.http://www.chinchilla-sounds.de/index_en.htm Since they are active at night, it is not uncommon for them to vocalize in the early hours of the morning. Chinchillas can be housed with others of the same sex, as long as they do not fight. Fighting or getting along depends on the individual animals. Conflict can be reduced provided the chinchillas are either introduced when young, or if older, are introduced gradually. Males and females will get along well, although they must be spayed or neutered to avoid reproduction. Since chinchillas are very active animals, it is preferred to house them in a large enclosure, such as a room of their own instead of a small cage. If kept in a cage, the chinchillas should have a large area replete with shelves or other obstacles on which to play. The cage should be taller than it is wide, as the chinchilla's natural environment is very mountainous. Chinchillas also need other forms of stimulation, such hanging wooden toys, large wheels (over 16 inches in diameter and not constructed of mesh, as chinchilla legs and toes can easily get caught), or paper towel tubes. Wooden sticks and chew toys are also good options, but conifer woods (especially cedar) should be avoided because of high content of resins that are toxic for chinchillas. Birch, willow, apple tree or manzanita are all safe woods for chinchillas to chew.http://www.chinchillas2home.co.uk/safewoods.htm Plastic in the cage should be avoided at all times. Chinchillas are often voracious chewers, and any ingested plastic can cause blockage in the intestines. As with most small animals, red cedar bedding should never be used due to its toxic nature.http://exoticpets.about.com/cs/guineapigs/a/woodshavings.htm The cage must have good air circulation. The chinchilla lacks the ability to sweat; therefore, if temperatures get above 25°C (77°F), the chinchilla could get overheated and may suffer from heat stroke.http://www.chin-chillas.com/heat_stroke.htm Active and inquisitive by nature, chinchillas need to spend some time outside of the cage (around half an hour a day and always supervised) to exercise and to satisfy their curiosity. Chinchillas can be found in a variety of colours including the standard grey (the only color found in nature), beige, ebony, and many others.http://www.gcchinchillas.com/colourchart.php They instinctively clean their fur by taking dust baths several times a week, in which they roll around in a container full of special chinchilla dust made of sand or fine pumice. It is important that if a chinchilla should get wet to carefully dry them quickly because their fur retains the moisture and can grow fungus or rot if not dried quickly with a blow dryer on a low, cool setting OR preferably gently with a towel.http://www.chincare.com/HealthLifestyle/GroomingFurHealth.htm Chinchillas have evolved to eat and digest desert grasses and cannot efficiently process fatty foods or too many green plants. A high quality, hay-based pellet and a constant supply of loose hay will sufficiently meet all of their dietary needs.http://www.chincare.com/HealthLifestyle/NutritionDental.htm An occasional treat of a raisin or other dried fruit is fine, but can easily be overdone, leading to diarrhea, or in the long term, diabetes. Keep in mind that some Chinchilla feed includes raisins as part of the mix. Fresh vegetables (with high moisture content) should be avoided as these can cause bloat in a chinchilla, which can be fatal. Chinchillas also eat in very small amounts and do the same with drinking water. Therefore, overfeeding is easy.http://www.naturecoastchinchillas.com/info.html Nuts should be avoided due to their high fat content.http://www.chincare.com/HealthLifestyle/NutritionDental.htm#treats A water bottle with fresh water should always be available. In scientific research Due to the fact that the chinchilla range of hearing (20 Hz to 30 kHz) is so close to that of a human, it is often used as an animal model in researching the auditory system.http://www.pirweb.org/pir04b_chinchilla.htm Other research fields in which chinchilla is used as an animal model include study of Chagas disease, Gastrointestinal disorders, Pneumonia, Listeriosis, as well as of Yersinia and Pseudomonas infections. See also * Viscacha References *Ades, H. W., Trahiotis, C., Kokko-Cunningham, A., & Averbuch, A. (1974). Comparison of hearing thresholds and morphological changes in the chinchilla after exposure to 4 kHz tones: Acta Oto-Laryngologica Vol 78(3-4) Sep-Oct 1974, 192-206. *Alkhatib, A., Biebel, U. W., & Smolders, J. W. T. (2006). Reduction of inhibition in the inferior colliculus after inner hair cell loss: Neuroreport: For Rapid Communication of Neuroscience Research Vol 17(14) Oct 2006, 1493-1497. *Arehole, S., Salvi, R. J., Saunders, S. S., & Gratton, M. A. (1989). Evoked-response forward-masking functions in chinchillas with noise-induced permanent hearing loss: Audiology Vol 28(2) Mar-Apr 1989, 92-110. *Arnold, S., & Burkard, R. (2000). Studies of interaural attenuation to investigate the validity of a dichotic difference tone response recorded from the inferior colliculus in the chinchilla: Journal of the Acoustical Society of America Vol 107(3) Mar 2000, 1541-1547. *Benson, D. A. (1974). An electrophysiological study of binaural interaction in the chinchilla auditory cortex: Dissertation Abstracts International. *Benson, D. A., & Teas, D. C. (1976). Single unit study of binaural interaction in the auditory cortex of the chinchilla: Brain Research Vol 103(2) 1976, 313-338. *Bowe, C. A., Miller, J. D., & Green, L. (1987). Qualities and locations of stimuli and responses affecting discrimination learning of chinchillas (Chinchilla laniger) and pigeons (Columba livia): Journal of Comparative Psychology Vol 101(2) Jun 1987, 132-138. *Brozoski, T. J., Bauer, C. A., & Caspary, D. M. (2002). Elevated fusiform cell activity in the dorsal cochlear nucleus of chinchillas with psychophysical evidence of tinnitus: Journal of Neuroscience Vol 22(6) Mar 2002, 2383-2390. *Burdick, C. K. (1976). Conditioning the chinchilla to indicate a sound-quality difference using a two-choice procedure: Dissertation Abstracts International. *Burdick, C. K. (1980). Auditory discrimination learning by the chinchilla: Comparison of go/no go and two-choice procedures: Journal of Auditory Research Vol 20(1) Jan 1980, 1-29. *Burdick, C. K., & Luz, G. A. (1973). Consummatory drinking of the chinchilla: Bulletin of the Psychonomic Society Vol 2(5-A) Nov 1973, 266-268. *Burdick, C. K., & Miller, J. D. (1973). New procedure for training chinchillas for psychoacoustic experiments: Journal of the Acoustical Society of America Vol 54(3) Sep 1973, 789-792. *Burkard, R., Trautwein, P., & Salvi, R. (1997). The effects of click level, click rate, and level of background masking noise on the inferior colliculus potential (ICP) in the normal and carboplatin-treated chinchilla: Journal of the Acoustical Society of America Vol 102(6) Dec 1997, 3620-3627. *Burkard, R. F., Secor, C. A., & Salvi, R. J. (1999). Near-field responses from the round window, inferior colliculus, and auditory cortex of the unanesthetized chinchilla: Manipulations of noiseburst level and rate: Journal of the Acoustical Society of America Vol 106(1) Jul 1999, 304-312. *Carman, J. B. (1974). Acquisition and extinction of shuttlebox avoidance in chinchilla ( Chinchilla lanigera ): Psychological Reports Vol 35(1, Pt 1) Aug 1974, 99-105. *Davis, R. I. (1982). Comparison between auditory electrophysiological and behavioral responses in normally and abnormally hearing chinchillas: Dissertation Abstracts International. *Delano, P. H., Elgueda, D., Hamame, C. M., & Robles, L. (2007). Selective attention to visual stimuli reduces cochlear sensitivity in chinchillas: Journal of Neuroscience Vol 27(15) Apr 2007, 4146-4153. *Dyer, R. S., Hammond, M. A., Weldon, D. A., & Booker, T. C. (1975). Influence of enucleation upon two-way avoidance behavior of rats, hamsters, chinchillas and BALB/cJ mice: Physiology & Behavior Vol 14(2) Feb 1975, 211-216. *El-Badry, M. M., Ding, D.-l., McFadden, S. L., & Eddin, A. C. (2007). Physiological effects of auditory nerve myelinopathy in chinchillas: European Journal of Neuroscience Vol 25(5) Mar 2007, 1437-1446. *El-Badry, M. M., & McFadden, S. L. (2007). Electrophysiological correlates of progressive sensorineural pathology in carboplatin-treated chinchillas: Brain Research Vol 1134 Feb 2007, 122-130. *Gerhardt, K. J., & Walton, J. P. (1986). Binaural acoustic reflex activity following monaural noise exposure in decerebrate chinchillas: Audiology Vol 25(4-5) Jul-Oct 1986, 309-320. *Graf, C. J., Saunders, S. S., & Salvi, R. J. (1992). Detection of intensity decrements by the chinchilla: Journal of the Acoustical Society of America Vol 91(2) Feb 1992, 1062-1068. *Halpern, D. L. (1985). Auditory filter shapes in the chinchilla: A behavioral investigation: Dissertation Abstracts International. *Hamernik, R. P., Ahroon, W. A., Patterson, J. H., Jr., & Qiu, W. (2002). Relations among early postexposure noise-induced threshold shifts and permanent threshold shifts in the chinchilla: Journal of the Acoustical Society of America Vol 111(1,Pt1) Jan 2002, 320-326. *Harrison, R. V. (2001). Age-related tonotopic map plasticity in the central auditory pathways: Scandinavian Audiology Vol 30(Suppl53) 2001, 8-14. *Henderson, D., & et al. (1973). Evoked-response audibility curve of the chinchilla: Journal of the Acoustical Society of America Vol 54(4) Oct 1973, 1099-1101. *Henderson, D., Hamernik, R. P., Salvi, R. J., & Ahroon, A. (1983). Comparison of auditory-evoked potentials and behavioral thresholds in the normal and noise-exposed chinchilla: Audiology Vol 22(2) Mar-Apr 1983, 172-180. *Hunter-Duvar, I. M., & Bredberg, G. (1974). Effects of intense auditory stimulation: Hearing losses and inner ear changes in the chinchilla: Journal of the Acoustical Society of America Vol 55(4) Apr 1974, 795-801. *James, A. L., Harrison, R. V., Pienkowski, M., Dajani, H. R., & Mount, R. J. (2005). Dynamics of real time DPOAE contralateral suppression in chinchillas and humans: International Journal of Audiology Vol 44(2) Feb 2005, 118-129. *Kokko-Cunningham, A., & Ades, H. W. (1976). Acetylcholinesterase activity in the chinchilla organ of Corti in normal and acoustically overstimulated animals: Acta Oto-Laryngologica Vol 81(1-2) Jan-Feb 1976, 48-56. *Kuhl, P. K., & Miller, J. D. (1975). Speech perception by the chinchilla: Voiced-voiceless distinction in alveolar plosive consonants: Science Vol 190(4209) Oct 1975, 69-72. *Leibrecht, B. C., & Kemmerer, W. S. (1974). Varieties of habituation in the chinchilla (Chinchilla lanigera): Journal of Comparative and Physiological Psychology Vol 86(1) Jan 1974, 124-132. *Li, H. (2003). Responses of inferior colliculus neurons to sinusoidal amplitude modulation in chinchillas. Dissertation Abstracts International: Section B: The Sciences and Engineering. *Lipscomb, D. M., & et al. (1977). The effect of high level sound on hearing sensitivity, cochlear sensorineuroepithelium and vasculature of the chinchilla: Acta Oto-Laryngologica Vol 84(1-2) Jul-Aug 1977, 44-56. *Luz, G. A., & Lipscomb, D. M. (1973). Susceptibility to damage from impulse noise: Chinchilla versus man or monkey: Journal of the Acoustical Society of America Vol 54(6) Dec 1973, 1750-1754. *McDowell, K. P. (1977). Auditory evoked response threshold shifts and surface damage to the organ of Corti in the chinchilla resulting from moderate intensity, long duration noise exposures: Dissertation Abstracts International. *McFadden, S. L., & Campo, P. (1998). Cubic distortion product otoacoustic emissions in young and aged chinchillas exposed to low-frequency noise: Journal of the Acoustical Society of America Vol 104(4) Oct 1998, 2290-2297. *McFadden, S. L., Henderson, D., & Quaranta, A. (1997). Remote masking in normal-hearing and noise-exposed chinchillas: Audiology & Neurotology Vol 2(3) May-Jun 1997, 128-138. *McFadden, S. L., Zheng, X.-Y., & Ding, D.-L. (2000). Conditioning-induced protection from impulse noise in female and male chinchillas: Journal of the Acoustical Society of America Vol 107(4) Apr 2000, 2162-2168. *Mills, J. H. (1973). Thresholds shifts produced by exposure to noise in chinchillas with noise-induced hearing losses: Journal of Speech & Hearing Research Vol 16(4) Dec 1973, 700-708. *Nelson, D. A., Kiester, T. E., Turner, C. W., & Ward, W. D. (1976). Automated conditioned-avoidance audiometry in the chinchilla: Journal of Auditory Research Vol 16(4) 1976, 209-237. *Niemiec, A. J., Yost, W. A., & Shofner, W. P. (1992). Behavioral measures of frequency selectivity in the chinchilla: Journal of the Acoustical Society of America Vol 92(5) Nov 1992, 2636-2649. *Ohlemiller, K. K., Jones, L. B., Heidbreder, A. F., Clark, W. W., & Miller, J. D. (1999). Voicing judgements by chinchillas trained with a reward paradigm: Behavioural Brain Research Vol 100(1-2) Apr 1999, 185-195. *Peters, E. N. (1965). Temporary shifts in auditory thresholds of chinchilla after exposure to noise: Journal of the Acoustical Society of America 37(5) 1965, 831-833. *Pienkowski, M., & Harrison, R. V. (2005). Tone Frequency Maps and Receptive Fields in the Developing Chinchilla Auditory Cortex: Journal of Neurophysiology Vol 93(1) Jan 2005, 454-466. *Pierrel-Sorrentino, R., & Raslear, T. G. (1980). Loudness scaling in rats and chinchillas: Journal of Comparative and Physiological Psychology Vol 94(4) Aug 1980, 757-766. *Prosen, C. A., Halpern, D. L., & Dallos, P. (1989). Frequency difference limens in normal and sensorineural hearing impaired chinchillas: Journal of the Acoustical Society of America Vol 85(3) Mar 1989, 1302-1313. *Recio, A. (2001). Representation of harmonic complex stimuli in the ventral cochlear nucleus of the chinchilla: Journal of the Acoustical Society of America Vol 110(4) Oct 2001, 2024-2033. *Salvi, R. J. (1976). The effects of TTS-producing tones on single neurons in the cochlear nucleus of the chinchilla: Dissertation Abstracts International. *Saunders, S. S., Shivapuja, B. G., & Salvi, R. J. (1987). Auditory intensity discrimination in the chinchilla: Journal of the Acoustical Society of America Vol 82(5) Nov 1987, 1604-1607. *Shofner, W. P., Yost, W. A., & Whitmer, W. M. (2007). Pitch perception in chinchillas (Chinchilla laniger): Stimulus generalization using rippled noise: Journal of Comparative Psychology Vol 121(4) Nov 2007, 428-439. *Sinex, D. G., & Havey, D. C. (1986). Neural mechanisms of tone-on-tone masking: Patterns of discharge rate and discharge synchrony related to rates of spontaneous discharge in the chinchilla auditory nerve: Journal of Neurophysiology Vol 56(6) Dec 1986, 1763-1780. *Takeno, S., Wake, M., Mount, R. J., & Harrison, R. V. (1998). Degeneration of spiral ganglion cells in the chinchilla after inner hair cell loss induced by carboplatin: Audiology & Neurotology Vol 3(5) Sep-Oct 1998, 281-290. *Wall, L. G., Ferraro, J. A., & Dunn, D. E. (1981). Temporal integration in the chinchilla: Journal of Auditory Research Vol 21(1) Jan 1981, 29-39. *Wall, L. R. (1979). Temporal integration in the chinchilla: Dissertation Abstracts International. *Wood, W. S. (1981). Effects of three noise exposure patterns with equivalent sound energy on the auditory system of chinchilla: Dissertation Abstracts International. *Woodford, C. (1977). Asymptotic noise-induced temporary threshold shift in chinchilla measured by the auditory evoked response: Audiology Vol 16(1) 1977, 11-20. *Young, J. S. (1981). Equal loudness and loudness scaling in the chinchilla: A reaction time procedure: Dissertation Abstracts International. External links * Save the Wild Chinchillas - An organization dedicated to preserving wild chinchilla populations. Category:Chinchillidae Category:Rodents Category:Mammals